CA2291691A1 - Device for counting fish population passing through a fish pass - Google Patents
Device for counting fish population passing through a fish pass Download PDFInfo
- Publication number
- CA2291691A1 CA2291691A1 CA002291691A CA2291691A CA2291691A1 CA 2291691 A1 CA2291691 A1 CA 2291691A1 CA 002291691 A CA002291691 A CA 002291691A CA 2291691 A CA2291691 A CA 2291691A CA 2291691 A1 CA2291691 A1 CA 2291691A1
- Authority
- CA
- Canada
- Prior art keywords
- fish
- time
- linear
- selected point
- line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 241000251468 Actinopterygii Species 0.000 title claims abstract description 113
- 238000006073 displacement reaction Methods 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 43
- 230000002045 lasting effect Effects 0.000 claims description 3
- 230000015654 memory Effects 0.000 abstract description 6
- 235000019688 fish Nutrition 0.000 description 85
- 230000009182 swimming Effects 0.000 description 11
- 238000011144 upstream manufacturing Methods 0.000 description 4
- 241000972773 Aulopiformes Species 0.000 description 3
- 235000019515 salmon Nutrition 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000001444 catalytic combustion detection Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010191 image analysis Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06M—COUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
- G06M1/00—Design features of general application
- G06M1/08—Design features of general application for actuating the drive
- G06M1/10—Design features of general application for actuating the drive by electric or magnetic means
- G06M1/101—Design features of general application for actuating the drive by electric or magnetic means by electro-optical means
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01K—ANIMAL HUSBANDRY; CARE OF BIRDS, FISHES, INSECTS; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
- A01K61/00—Culture of aquatic animals
- A01K61/90—Sorting, grading, counting or marking live aquatic animals, e.g. sex determination
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
- G01B11/04—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness specially adapted for measuring length or width of objects while moving
- G01B11/043—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness specially adapted for measuring length or width of objects while moving for measuring length
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
- G01P3/64—Devices characterised by the determination of the time taken to traverse a fixed distance
- G01P3/68—Devices characterised by the determination of the time taken to traverse a fixed distance using optical means, i.e. using infrared, visible, or ultraviolet light
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
- G01P3/64—Devices characterised by the determination of the time taken to traverse a fixed distance
- G01P3/80—Devices characterised by the determination of the time taken to traverse a fixed distance using auto-correlation or cross-correlation detection means
- G01P3/806—Devices characterised by the determination of the time taken to traverse a fixed distance using auto-correlation or cross-correlation detection means in devices of the type to be classified in G01P3/68
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06M—COUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
- G06M11/00—Counting of objects distributed at random, e.g. on a surface
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06M—COUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
- G06M7/00—Counting of objects carried by a conveyor
Abstract
A fish population counting device for counting the number of fish passing through the fish pass according to directions and fish sizes. Image data produced by the two-line camera (1) that takes pictures simultaneously on two shooting lines (A, B) is sent through the A/D converter (2) and stored one line at a time in image memories (3A, 3B). The image data is then transferred to the processing unit (6), where they are rearranged in the order of shooting for each shooting line (A, B) to generate two-line successive images (A, B).
From these two-line successive images (A, B), the outlines of the areas whose label numbers are the same are traced to separate massive figures scattered in the images. The features of the massive figures are extracted and matched against a standard pattern to decide if the massive figures are fish or not.
Then, the positions and shapes of all fish scattered in the two-line successive images (A, B) are identified one by one to count the number of fish that have passed through the shooting lines (A, B) during a predetermined length of time. Further, individual fish that are at displaceable positions are taken to be the same fish and, based on the displacements of these fish, the directions and speeds of these individual fish are calculated. From the fish speeds the size of each fish is determined. The number of fish is counted by the size and the direction.
From these two-line successive images (A, B), the outlines of the areas whose label numbers are the same are traced to separate massive figures scattered in the images. The features of the massive figures are extracted and matched against a standard pattern to decide if the massive figures are fish or not.
Then, the positions and shapes of all fish scattered in the two-line successive images (A, B) are identified one by one to count the number of fish that have passed through the shooting lines (A, B) during a predetermined length of time. Further, individual fish that are at displaceable positions are taken to be the same fish and, based on the displacements of these fish, the directions and speeds of these individual fish are calculated. From the fish speeds the size of each fish is determined. The number of fish is counted by the size and the direction.
Description
SPECIFICATION
Device for Counting Fish Population Passing through a Fish Pass Technical Field:
The present invention relates to a device for automatically counting fishes passing through a selected point in a given narrow water passage.
Related Background Art:
Hitherto, fishes passing through a selected point in a given water passage have been counted by sight by persons standing at selected places along the water passage. Such counting, however, is difficult to be continued an elongated time without lowering the accuracy. -It has been proposed that pictures of fishes are taken by a piece of electronic equipment used to take pictures (called hereinafter "Video Camera" or "Camera"), which is set at a selected point in a given water passage, and that the pictures are analyzed to determine the number of fishes passing through the selected point in the water passage.
The video camera takes pictures intermittently, for example, one each 1/30 seconds. The number of fishes, therefore, cannot be determined without taking account of displacements of fish images by comparing two subsequent pictures all the time.
The video camera has a relatively wide range of horizontal view.
It is, therefore, necessary that the video camera be protected against the reflection of surrounding light from the water surface. For examples, the area of the water surface which the video camera can span is covered by anti-reflection sheet, or otherwise, the video camera is put in a water-proof enclosure to be submerged below the water surface.
With a view to solve these problems the same applicant as the present application filed a patent application disclosing a device for taking pictures of fishes passing through a selected point in a given narrow water passage with a linear video camera to analyze and determine the number of fishes from such pictures (see Japanese Patent Application Laid-Open No.6-196139).
Disadvantageously this counting device is insensible to the direction in which fishes swim to pass through the selected point in the water passage, so that it cannot make any decision as to whether the so counted fishes swim upstream or downstream.
Fish images appearing in the pictures taken by the linear video camera are liable for their total lengths to vary with swimming speed; the image of fishes of same length is shortened when the fishes pass through the selected point quickly whereas the image of fishes of same length is elongated when the fishes pass through the selected point slowly.
Therefore, the fish size cannot be determined, and the number of fishes cannot be determined in terms of kinds, which may be given in terms of size. Assume that salmon passing through a selected point in the water passage are counted, and that small fishes other than salmon swim slowly, such foreign fishes are erroneously counted to yield a wrong count of salmons.
In view of the above the object of the present invention is to provide a fish counting device which is sensible to the size of fishes, in terms of which fish kinds can be determined, thereby permitting the counting of fishes in terms of fish kinds, and which is sensible to in which direction fishes pass through the selected point.
Disclosure of the Invention:
A device for counting fish population passing through a selected point in a given water passage comprises:
a two-line camera for taking linear pictures along two parallel lines traversing the water passage at regular time intervals to store the linear-dimensional image data;
means for providing two time-sequential arrangements of the linear-dimensional image data of the pictures taken for a predetermined length of time, each representing the time-sequential event as viewed from each line;
means for retrieving different shapes appearing in the time-sequential event thus represented;
means for determining whether each of the so retrieved shapes is a fish or not;
means for comparing the so determined fish shapes appearing in one of the two time-sequential arrangement of linear pictures with those appearing in the other time sequential arrangement of linear pictures in terms of their relative positions to determine the displacement of each fish shape;
means responsive to the so determined displacement of each fish for determining in which direction the fish shape passes through the selected point in the water passage;
means for determining the speed of each fish shape from its displacement; and means for determining the time taken for each fish shape to pass through the selected point, lasting from the instant at which the mouth of the fish shape reaches the selected point to the instant at which the caudal fin of the fish shape leaves the selected point, and for determining the fish size from the so determined time and speed, whereby the number of fish passing through the selected point for the predetermined length of time may be determined in terms of the fish size and the direction.
Brief Description of the Drawings:
Fig.1 is a block diagram showing a device for counting fish population passing through a selected point in a given water passage according to the present invention;
Fig.2 is a side view of the water passage, illustrating how a two-line camera is positioned;
Fig.3 is a plane view of the water passage, illustrating how the two-line camera is positioned;
Fig.4 is a flow chart representing the image-processing effected in the fish population counting device;
Fig.S illustrates examples of two time-sequential arrangements of the linear-dimensional image data, each representing the time-sequential event as viewed from each line;
Fig.6 illustrates two time-sequential arrangements of linear pictures A and B, indicating that fish shapes move from the picture-taking line A to the picture-taking line B; and Fig.7 illustrates two time-sequential arrangements of linear pictures A and B, indicating that fish shapes move from the picture-taking line B to the picture-taking line A.
Best Mode of Reducing the Invention to Practice:
With reference to the accompanying drawings a preferable embodiment of the present invention is described below.
Fig.l is a block diagram showing a device for counting fish population passing through a selected point in a given water passage according to the present invention.
In Fig.l parts 1 to 3 make up a recording section for recording the sequential pictures of two parallel, linear areas selected in the water passage, and parts 6 and 7 make up an analyzing section for analyzing the image data of the pictures recorded in the recording section. A two-line camera 1 takes two linear-pictures simultaneously.
A linear camera uses a linear sensor as photoelectric converter.
The linear sensor is a signal-transferring type of image sensor, which is composed of a linear arrangement of light-receiving elements such as CCDs.
The two-line camera may be a set of two linear cameras arranged front and rear, or a single camera having a prism for separating a single optical axis into two divisional axes each directed to two linear sensors for taking the pictures of two linear zones simultaneously.
Pieces of information of color densities provided by the two-line camera 1 are converted by an A/D converter 2 to be stored for each of the two linear zones simultaneously in two image memories 3A and 3B.
A display device 4 shows the contents of the image memories 3A
and 3B in the form of separate pictures.
A controller 5 controls the two-line camera 1, the A/D converter 2 and the image memories 3A and 3B according to a predetermined proceeding.
An image processing unit 6 includes a computer and other electronics for taking in required data and for effecting required image analyses.
The image processing unit 6 stores reference fish patterns relative to which a decision can be made as to whether the moving objects appearing in the pictures are fish or not.
A display 7 shows a series of pictures of the water passage taken by the two-line camera 1 along with the results of measurement.
Now, one example of counting fish population passing through a selected point in a given water passage is described.
Referring to Figs.2 and 3, a light-projecting unit 8 is laid on the bed of the water passage to throw the beam of light upward, traversing the water passage laterally along two picture-taking lines A and B.
The light-projecting unit 8 comprises a spot light source 8a and a spot-to-linear beam converter 8c connected to the spot light source 8a via a length of optical fiber 8b.
The two-line camera 1 is positioned just above the picture-taking lines A and B, thus permitting the taking of the pictures of the linear zones of water passage defined by the lines A and B respectively.
Three to five hundred pictures are taken each second.
The two-line camera needs to be positioned above the water passage, but the other units may be put (several hundred meters) apart from the water passage.
It is of most concern to select the place where the two-line camera is positioned.
The lateral dimension (perpendicular to the water passage) of each linear zone is equal to the width of the water passage whereas the longitudinal dimension (parallel to the water passage) is several millimeters to one centimeter long (dependent on required precision or the width of the water passage).
The picture-taking lines A and B are separated several millimeters to approximately ten centimeters (two linear cameras arranged front and rear) apart from each other.
The two-line camera 1 is fixed to a support board, which is 20 cm wide to suppress undesired reflection of light in the picture-taking area.
The two-line camera 1 is relatively light, and therefore, it suffices that the support board be strong enough to support its own weight.
A bridge across the water passage may be used to hold the two-line camera above the water passage, provided that the height from the water passage is permitted.
The raised level at which the two-line camera 1 is positioned above the water passage can be determined from the focal length of the lens although the width of the water passage and surrounding conditions still remain as factors for determining the raised level at which the camera is positioned.
Referring to Fig.4, the manner in which images are processed in the fish population counting device is described.
At first, the two-line camera 1 takes linear pictures along two parallel lines A and B simultaneously.
The linear sensors of the two-line camera 1 provide analog data of the so taken pictures sequentially at their output terminals.
The data thus outputted are converted to corresponding digital data by the A/D converter 2 to be stored for each linear picture in the image memories 3A and 3B allotted to the picture-taking lines A and B
reapectively.
The image data are transferred from the image memories 3A and 3B
to the image processing unit 6 (S1).
The image processing unit 6 provides two time-sequential arrangements of the linear-dimensional image data or linear pictures A and B (see Fig.S), each representing the time-sequential event as viewed from each picture-taking line A or B (S2).
The two time-sequential arrangements of linear pictures A and B
are scanned across their whole areas to distinguish areas in terms of their color densities for separating different shapes of one color density from those of the other color density (S3).
Different shapes of one or the other color density are compared with the reference fish patterns representing fish shapes to make a decision as to whether they are fish or not (S4).
Each and every fish shape in the two time-sequential arrangements of linear pictures A and B is determined in its shape and position to calculate the number of fish shapes passing through the picture-taking lines -s-A and B for the predetermined length of time (SS).
Each and every fish shape in the two time-sequential arrangements of linear pictures A and B is compared to determine which fish shapes are within a presumable distance, regarding the two fish shapes thus found within the presumable distance as one and same fish shape, thus determining the swimming direction and speed from the displacement of one and same fish shape (S6). Two fish shapes appearing apart from the presumable distance( or too apart from the distance within which one and same fish can move in a certain limited time) in the two time-sequential arrangements of linear pictures are different fish shapes.
The time taken for each fish shape to pass through the selected point is determined, lasting from the instant at which the mouth of the fish shape reaches the selected point to the instant at which the caudal fin of the fish shape leaves the selected point, and the fish size is determined from the so determined time and the swimming speed already determined.
Thus, the number of fish passing through the selected point for the predetermined length of time are determined in terms of the fish sizes (i.e.
fish kinds) and the swimming direction.
The pieces of information thus collected are shown along with time indication in the display 7 (S8).
As for determination of the swimming direction: referring to Fig.6, a fish shape appears first in the time-sequential arrangement of linear pictures A which shows an earlier event in the water passage (at early time tl), and then the fish shape appears in the time-sequential arrangement of linear pictures B which shows a sequential or later event in the water passage (at later time t2), and then it is determined that the fish shape moves from the picture-taking line A to the picture-taking line B.
Referring to Fig.7, conversely, a fish shape appears first in the time-sequential arrangement of linear pictures B (at early time t1), and then the fish shape appears in the time-sequential arrangement of linear pictures A (at later time t2), and then it is determined that the fish shape moves from the picture-taking line B to the picture-taking line A.
As seen from Figs.6 and 7, when image data are arranged in the order in which pictures were taken, every fish shape is directed with its mouth up and its caudal fin down whether it swims upstream or downstream; the fish swims with its mouth directed in the direction in which it swims all the time no matter in which direction it may swim, upstream or downstream.
As for the swimming speed: from the time interval between time t1 and time t2 in the time-sequential arrangements of linear pictures A and B
it can be determined how long it takes to pass from the picture-taking line A (or B) to the picture-taking line B (or A), and the swimming speed can be determined by dividing the distance between the picture-taking lines A and B by the so determined length of time.
Industrial Utility:
As may be understood from the above, two linear pictures traversing a given water passage at a selected point are taken simultaneously to provide two series of time-sequential arrangement of linear pictures, thereby permitting measurement of the displacement of each and every fish shape in terms of fish positions appearing in the two series of time-sequential arrangement of linear pictures to determine the swimming direction and speed of each and every fish in the water passage.
Thus, the numbers of fishes swimming upstream or downstream can be counted respectively in terms of swimming directions.
Also, the fish size can be determined from the swimming speed and the time difference between the instant at which the mouth of the fish reaches the selected point and the instant at which the tail fin of the fish leaves the selected point in the water passage. Thus, the numbers of fishes can be counted in terms of fish sizes or kinds.
Device for Counting Fish Population Passing through a Fish Pass Technical Field:
The present invention relates to a device for automatically counting fishes passing through a selected point in a given narrow water passage.
Related Background Art:
Hitherto, fishes passing through a selected point in a given water passage have been counted by sight by persons standing at selected places along the water passage. Such counting, however, is difficult to be continued an elongated time without lowering the accuracy. -It has been proposed that pictures of fishes are taken by a piece of electronic equipment used to take pictures (called hereinafter "Video Camera" or "Camera"), which is set at a selected point in a given water passage, and that the pictures are analyzed to determine the number of fishes passing through the selected point in the water passage.
The video camera takes pictures intermittently, for example, one each 1/30 seconds. The number of fishes, therefore, cannot be determined without taking account of displacements of fish images by comparing two subsequent pictures all the time.
The video camera has a relatively wide range of horizontal view.
It is, therefore, necessary that the video camera be protected against the reflection of surrounding light from the water surface. For examples, the area of the water surface which the video camera can span is covered by anti-reflection sheet, or otherwise, the video camera is put in a water-proof enclosure to be submerged below the water surface.
With a view to solve these problems the same applicant as the present application filed a patent application disclosing a device for taking pictures of fishes passing through a selected point in a given narrow water passage with a linear video camera to analyze and determine the number of fishes from such pictures (see Japanese Patent Application Laid-Open No.6-196139).
Disadvantageously this counting device is insensible to the direction in which fishes swim to pass through the selected point in the water passage, so that it cannot make any decision as to whether the so counted fishes swim upstream or downstream.
Fish images appearing in the pictures taken by the linear video camera are liable for their total lengths to vary with swimming speed; the image of fishes of same length is shortened when the fishes pass through the selected point quickly whereas the image of fishes of same length is elongated when the fishes pass through the selected point slowly.
Therefore, the fish size cannot be determined, and the number of fishes cannot be determined in terms of kinds, which may be given in terms of size. Assume that salmon passing through a selected point in the water passage are counted, and that small fishes other than salmon swim slowly, such foreign fishes are erroneously counted to yield a wrong count of salmons.
In view of the above the object of the present invention is to provide a fish counting device which is sensible to the size of fishes, in terms of which fish kinds can be determined, thereby permitting the counting of fishes in terms of fish kinds, and which is sensible to in which direction fishes pass through the selected point.
Disclosure of the Invention:
A device for counting fish population passing through a selected point in a given water passage comprises:
a two-line camera for taking linear pictures along two parallel lines traversing the water passage at regular time intervals to store the linear-dimensional image data;
means for providing two time-sequential arrangements of the linear-dimensional image data of the pictures taken for a predetermined length of time, each representing the time-sequential event as viewed from each line;
means for retrieving different shapes appearing in the time-sequential event thus represented;
means for determining whether each of the so retrieved shapes is a fish or not;
means for comparing the so determined fish shapes appearing in one of the two time-sequential arrangement of linear pictures with those appearing in the other time sequential arrangement of linear pictures in terms of their relative positions to determine the displacement of each fish shape;
means responsive to the so determined displacement of each fish for determining in which direction the fish shape passes through the selected point in the water passage;
means for determining the speed of each fish shape from its displacement; and means for determining the time taken for each fish shape to pass through the selected point, lasting from the instant at which the mouth of the fish shape reaches the selected point to the instant at which the caudal fin of the fish shape leaves the selected point, and for determining the fish size from the so determined time and speed, whereby the number of fish passing through the selected point for the predetermined length of time may be determined in terms of the fish size and the direction.
Brief Description of the Drawings:
Fig.1 is a block diagram showing a device for counting fish population passing through a selected point in a given water passage according to the present invention;
Fig.2 is a side view of the water passage, illustrating how a two-line camera is positioned;
Fig.3 is a plane view of the water passage, illustrating how the two-line camera is positioned;
Fig.4 is a flow chart representing the image-processing effected in the fish population counting device;
Fig.S illustrates examples of two time-sequential arrangements of the linear-dimensional image data, each representing the time-sequential event as viewed from each line;
Fig.6 illustrates two time-sequential arrangements of linear pictures A and B, indicating that fish shapes move from the picture-taking line A to the picture-taking line B; and Fig.7 illustrates two time-sequential arrangements of linear pictures A and B, indicating that fish shapes move from the picture-taking line B to the picture-taking line A.
Best Mode of Reducing the Invention to Practice:
With reference to the accompanying drawings a preferable embodiment of the present invention is described below.
Fig.l is a block diagram showing a device for counting fish population passing through a selected point in a given water passage according to the present invention.
In Fig.l parts 1 to 3 make up a recording section for recording the sequential pictures of two parallel, linear areas selected in the water passage, and parts 6 and 7 make up an analyzing section for analyzing the image data of the pictures recorded in the recording section. A two-line camera 1 takes two linear-pictures simultaneously.
A linear camera uses a linear sensor as photoelectric converter.
The linear sensor is a signal-transferring type of image sensor, which is composed of a linear arrangement of light-receiving elements such as CCDs.
The two-line camera may be a set of two linear cameras arranged front and rear, or a single camera having a prism for separating a single optical axis into two divisional axes each directed to two linear sensors for taking the pictures of two linear zones simultaneously.
Pieces of information of color densities provided by the two-line camera 1 are converted by an A/D converter 2 to be stored for each of the two linear zones simultaneously in two image memories 3A and 3B.
A display device 4 shows the contents of the image memories 3A
and 3B in the form of separate pictures.
A controller 5 controls the two-line camera 1, the A/D converter 2 and the image memories 3A and 3B according to a predetermined proceeding.
An image processing unit 6 includes a computer and other electronics for taking in required data and for effecting required image analyses.
The image processing unit 6 stores reference fish patterns relative to which a decision can be made as to whether the moving objects appearing in the pictures are fish or not.
A display 7 shows a series of pictures of the water passage taken by the two-line camera 1 along with the results of measurement.
Now, one example of counting fish population passing through a selected point in a given water passage is described.
Referring to Figs.2 and 3, a light-projecting unit 8 is laid on the bed of the water passage to throw the beam of light upward, traversing the water passage laterally along two picture-taking lines A and B.
The light-projecting unit 8 comprises a spot light source 8a and a spot-to-linear beam converter 8c connected to the spot light source 8a via a length of optical fiber 8b.
The two-line camera 1 is positioned just above the picture-taking lines A and B, thus permitting the taking of the pictures of the linear zones of water passage defined by the lines A and B respectively.
Three to five hundred pictures are taken each second.
The two-line camera needs to be positioned above the water passage, but the other units may be put (several hundred meters) apart from the water passage.
It is of most concern to select the place where the two-line camera is positioned.
The lateral dimension (perpendicular to the water passage) of each linear zone is equal to the width of the water passage whereas the longitudinal dimension (parallel to the water passage) is several millimeters to one centimeter long (dependent on required precision or the width of the water passage).
The picture-taking lines A and B are separated several millimeters to approximately ten centimeters (two linear cameras arranged front and rear) apart from each other.
The two-line camera 1 is fixed to a support board, which is 20 cm wide to suppress undesired reflection of light in the picture-taking area.
The two-line camera 1 is relatively light, and therefore, it suffices that the support board be strong enough to support its own weight.
A bridge across the water passage may be used to hold the two-line camera above the water passage, provided that the height from the water passage is permitted.
The raised level at which the two-line camera 1 is positioned above the water passage can be determined from the focal length of the lens although the width of the water passage and surrounding conditions still remain as factors for determining the raised level at which the camera is positioned.
Referring to Fig.4, the manner in which images are processed in the fish population counting device is described.
At first, the two-line camera 1 takes linear pictures along two parallel lines A and B simultaneously.
The linear sensors of the two-line camera 1 provide analog data of the so taken pictures sequentially at their output terminals.
The data thus outputted are converted to corresponding digital data by the A/D converter 2 to be stored for each linear picture in the image memories 3A and 3B allotted to the picture-taking lines A and B
reapectively.
The image data are transferred from the image memories 3A and 3B
to the image processing unit 6 (S1).
The image processing unit 6 provides two time-sequential arrangements of the linear-dimensional image data or linear pictures A and B (see Fig.S), each representing the time-sequential event as viewed from each picture-taking line A or B (S2).
The two time-sequential arrangements of linear pictures A and B
are scanned across their whole areas to distinguish areas in terms of their color densities for separating different shapes of one color density from those of the other color density (S3).
Different shapes of one or the other color density are compared with the reference fish patterns representing fish shapes to make a decision as to whether they are fish or not (S4).
Each and every fish shape in the two time-sequential arrangements of linear pictures A and B is determined in its shape and position to calculate the number of fish shapes passing through the picture-taking lines -s-A and B for the predetermined length of time (SS).
Each and every fish shape in the two time-sequential arrangements of linear pictures A and B is compared to determine which fish shapes are within a presumable distance, regarding the two fish shapes thus found within the presumable distance as one and same fish shape, thus determining the swimming direction and speed from the displacement of one and same fish shape (S6). Two fish shapes appearing apart from the presumable distance( or too apart from the distance within which one and same fish can move in a certain limited time) in the two time-sequential arrangements of linear pictures are different fish shapes.
The time taken for each fish shape to pass through the selected point is determined, lasting from the instant at which the mouth of the fish shape reaches the selected point to the instant at which the caudal fin of the fish shape leaves the selected point, and the fish size is determined from the so determined time and the swimming speed already determined.
Thus, the number of fish passing through the selected point for the predetermined length of time are determined in terms of the fish sizes (i.e.
fish kinds) and the swimming direction.
The pieces of information thus collected are shown along with time indication in the display 7 (S8).
As for determination of the swimming direction: referring to Fig.6, a fish shape appears first in the time-sequential arrangement of linear pictures A which shows an earlier event in the water passage (at early time tl), and then the fish shape appears in the time-sequential arrangement of linear pictures B which shows a sequential or later event in the water passage (at later time t2), and then it is determined that the fish shape moves from the picture-taking line A to the picture-taking line B.
Referring to Fig.7, conversely, a fish shape appears first in the time-sequential arrangement of linear pictures B (at early time t1), and then the fish shape appears in the time-sequential arrangement of linear pictures A (at later time t2), and then it is determined that the fish shape moves from the picture-taking line B to the picture-taking line A.
As seen from Figs.6 and 7, when image data are arranged in the order in which pictures were taken, every fish shape is directed with its mouth up and its caudal fin down whether it swims upstream or downstream; the fish swims with its mouth directed in the direction in which it swims all the time no matter in which direction it may swim, upstream or downstream.
As for the swimming speed: from the time interval between time t1 and time t2 in the time-sequential arrangements of linear pictures A and B
it can be determined how long it takes to pass from the picture-taking line A (or B) to the picture-taking line B (or A), and the swimming speed can be determined by dividing the distance between the picture-taking lines A and B by the so determined length of time.
Industrial Utility:
As may be understood from the above, two linear pictures traversing a given water passage at a selected point are taken simultaneously to provide two series of time-sequential arrangement of linear pictures, thereby permitting measurement of the displacement of each and every fish shape in terms of fish positions appearing in the two series of time-sequential arrangement of linear pictures to determine the swimming direction and speed of each and every fish in the water passage.
Thus, the numbers of fishes swimming upstream or downstream can be counted respectively in terms of swimming directions.
Also, the fish size can be determined from the swimming speed and the time difference between the instant at which the mouth of the fish reaches the selected point and the instant at which the tail fin of the fish leaves the selected point in the water passage. Thus, the numbers of fishes can be counted in terms of fish sizes or kinds.
Claims
1. A device for counting fish population passing through a selected point in a given water passage comprises:
a two-line camera for taking linear pictures along two parallel lines traversing the water passage at regular time intervals to store the linear-dimensional image data;
means for providing two time-sequential arrangements of the linear-dimensional image data of the pictures taken for a predetermined length of time, each representing the time-sequential event as viewed from each line;
means for retrieving different shapes appearing in the time-sequential event thus represented;
means for determining whether each of the so retrieved shapes is a fish or not;
means for comparing the so determined fish shapes appearing in one of the two time-sequential arrangements of linear pictures with those appearing in the other time sequential arrangement of linear pictures in terms of their relative positions to determine the displacement of each fish shape;
means responsive to the so determined displacement of each fish shape for determining in which direction the fish shape passes through the selected point in the water passage;
means for determining the speed of each fish shape from its displacement; and means for determining the time taken for each fish shape to pass through the selected point, lasting from the instant at which the mouth of the fish shape reaches the selected point to the instant at which the caudal fin of the fish shape leaves the selected point, and for determining the fish size from the so determined time and the speed of the fish shape already determined, whereby the number of fish passing through the selected point for the predetermined length of time may be determined in terms of the fish size and the direction.
a two-line camera for taking linear pictures along two parallel lines traversing the water passage at regular time intervals to store the linear-dimensional image data;
means for providing two time-sequential arrangements of the linear-dimensional image data of the pictures taken for a predetermined length of time, each representing the time-sequential event as viewed from each line;
means for retrieving different shapes appearing in the time-sequential event thus represented;
means for determining whether each of the so retrieved shapes is a fish or not;
means for comparing the so determined fish shapes appearing in one of the two time-sequential arrangements of linear pictures with those appearing in the other time sequential arrangement of linear pictures in terms of their relative positions to determine the displacement of each fish shape;
means responsive to the so determined displacement of each fish shape for determining in which direction the fish shape passes through the selected point in the water passage;
means for determining the speed of each fish shape from its displacement; and means for determining the time taken for each fish shape to pass through the selected point, lasting from the instant at which the mouth of the fish shape reaches the selected point to the instant at which the caudal fin of the fish shape leaves the selected point, and for determining the fish size from the so determined time and the speed of the fish shape already determined, whereby the number of fish passing through the selected point for the predetermined length of time may be determined in terms of the fish size and the direction.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JPPH9-155884 | 1997-05-29 | ||
| JP15588497 | 1997-05-29 | ||
| PCT/JP1998/002390 WO1998054671A1 (en) | 1997-05-29 | 1998-05-29 | Device for counting fish population passing through a fish pass |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2291691A1 true CA2291691A1 (en) | 1998-12-03 |
Family
ID=15615618
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002291691A Abandoned CA2291691A1 (en) | 1997-05-29 | 1998-05-29 | Device for counting fish population passing through a fish pass |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0984391A4 (en) |
| CA (1) | CA2291691A1 (en) |
| NO (1) | NO995826L (en) |
| WO (1) | WO1998054671A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2716418C1 (en) * | 2019-07-11 | 2020-03-11 | Общество с ограниченной ответственностью "Конструкторское бюро морской электроники "Вектор" (ООО КБМЭ "Вектор") | Fish counting device |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE60037360T2 (en) | 1999-05-28 | 2008-12-04 | Nippon Telegraph And Telephone Corp. | Method and device for measuring the speed of vehicles with an image processing system |
| JP3403697B2 (en) * | 1999-05-28 | 2003-05-06 | 日本電信電話株式会社 | Image processing method and apparatus |
| JP3783835B2 (en) * | 2000-05-12 | 2006-06-07 | 東光電気株式会社 | Quantity measuring device for fish going up the fishway |
| NO20033537D0 (en) * | 2003-08-11 | 2003-08-11 | Kristian Lillerud | Method and apparatus for counting and calculating weight in fish |
| DE202006007875U1 (en) * | 2006-05-15 | 2007-09-20 | Big Dutchman International Gmbh | Eierzählsensor |
| DE102007015320B4 (en) * | 2006-11-03 | 2008-10-23 | Basler Ag | Camera for analyzing objects |
| NO330863B1 (en) | 2007-07-09 | 2011-08-01 | Feed Control Norway As | Apparatus and method for cutting weight milling and appetite lining in fish farms |
| NL2002462C2 (en) * | 2009-01-29 | 2010-07-30 | Nedap Nv | METHOD FOR DETECTING, IN PARTICULAR COUNTING ANIMALS |
| US8651057B1 (en) | 2010-08-23 | 2014-02-18 | The United States Of America, As Represented By The Secretary Of The Interior | Photographic animal counter for monitoring movement of aquatic animals |
| NO332103B1 (en) * | 2010-12-13 | 2012-06-25 | Ocea As | System and method for calculating the size of marine organisms in water |
| WO2013141711A2 (en) * | 2012-03-23 | 2013-09-26 | Holts Jens Christian | Fish fence, and corresponding system. |
| FR3003381B1 (en) * | 2013-03-15 | 2016-07-15 | Jean Dartiguelongue | AUTOMATIC FISH COUNTING DEVICE |
| CN103766259B (en) * | 2014-01-26 | 2015-11-18 | 四川大学 | Fish Microexamination device |
| FR3030837B1 (en) * | 2014-12-18 | 2018-02-02 | Institut De Recherche Pour Le Developpement | METHOD FOR COUNTING AQUATIC SPECIES |
| WO2016107659A1 (en) * | 2014-12-31 | 2016-07-07 | Allegri Roberto | Arrangement and method for counting articles |
| CN107909137A (en) * | 2017-11-27 | 2018-04-13 | 南瑞集团有限公司 | A kind of fish pass crosses fish counting and recognition methods |
| AT523459B1 (en) * | 2020-01-21 | 2022-04-15 | Fishcon Gmbh | Device for detecting aquatic organisms |
| CN111650392A (en) * | 2020-07-03 | 2020-09-11 | 东北大学 | Metal sheet movement speed detection method based on linear array camera stereoscopic vision |
| CN112461157A (en) * | 2020-11-16 | 2021-03-09 | 国电大渡河枕头坝发电有限公司 | Fish passing monitoring system |
| CN112569598A (en) * | 2020-12-22 | 2021-03-30 | 上海幻电信息科技有限公司 | Target object control method and device |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61164118A (en) * | 1985-01-16 | 1986-07-24 | Mitsubishi Petrochem Co Ltd | Load meter |
| JPS63313069A (en) * | 1987-06-16 | 1988-12-21 | Matsushita Electric Ind Co Ltd | Method for detecting moving state of moving body |
| DK19992A (en) * | 1992-02-17 | 1993-08-18 | Reson System As | SYSTEM AND PROCEDURE FOR MEASURING AND / OR IDENTIFYING OBJECTS |
| JPH07128347A (en) * | 1993-11-05 | 1995-05-19 | Nec Corp | Optical imaging and processing type vehicle sensor |
| JPH0844843A (en) * | 1994-07-28 | 1996-02-16 | Kensetsu Gijutsu Kenkyusho:Kk | Analyzer for fish flow in fishway |
-
1998
- 1998-05-29 WO PCT/JP1998/002390 patent/WO1998054671A1/en not_active Application Discontinuation
- 1998-05-29 CA CA002291691A patent/CA2291691A1/en not_active Abandoned
- 1998-05-29 EP EP98921889A patent/EP0984391A4/en not_active Withdrawn
-
1999
- 1999-11-26 NO NO995826A patent/NO995826L/en not_active Application Discontinuation
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2716418C1 (en) * | 2019-07-11 | 2020-03-11 | Общество с ограниченной ответственностью "Конструкторское бюро морской электроники "Вектор" (ООО КБМЭ "Вектор") | Fish counting device |
Also Published As
| Publication number | Publication date |
|---|---|
| NO995826D0 (en) | 1999-11-26 |
| NO995826L (en) | 1999-11-26 |
| EP0984391A4 (en) | 2002-07-24 |
| WO1998054671A1 (en) | 1998-12-03 |
| EP0984391A1 (en) | 2000-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0984391A1 (en) | Device for counting fish population passing through a fish pass | |
| CA1236572A (en) | Machine readable markers for cartesian information storage media | |
| US4670659A (en) | Calibration method for an optical measuring system employing reference grids in a series of reference planes | |
| US20080137104A1 (en) | Method and Device for Recording and Determining the Weight of Fish | |
| US4842411A (en) | Method of automatically measuring the shape of a continuous surface | |
| US20020150308A1 (en) | Image processing method, and an apparatus provided with an image processing function | |
| FR2458830B1 (en) | OPTICAL REPRESENTATION SYSTEM PROVIDED WITH AN OPTOELECTRONIC DETECTION SYSTEM FOR DETERMINING A GAP BETWEEN THE IMAGE PLAN OF THE REPRESENTATION SYSTEM AND A SECOND PLAN FOR REPRESENTATION | |
| US6795200B1 (en) | Method and system for dimensioning boxes or other cuboid objects | |
| US5142160A (en) | Method and device for determining the volume of an object on a flat background | |
| CN101218602A (en) | Image processor and environment information observing device | |
| ATE43716T1 (en) | METHOD FOR PHOTOGRAMMETRIC DETECTION OF AN OBJECT USING AT LEAST ONE SOLID-BODY OPTOELECTRIC AREA SENSOR. | |
| Yanai et al. | Three-dimensional videography of swimming with panning periscopes | |
| JPS57161839A (en) | Distance measuring device of camera | |
| EP0282517B1 (en) | Apparatus for determining the real or virtual distance of a light source from a measurement plane | |
| JPS63133061A (en) | Fish living condition monitoring instrument | |
| US4924505A (en) | Method of mensuration of an image on an object | |
| WO1985002284A1 (en) | Machine readable markers for cartesian information storage media | |
| US4897678A (en) | Double z-axis translational mounting apparatus for camera in photogrammetry mensuration systems | |
| ATE123196T1 (en) | DEVICE AND METHOD FOR MOTION DETECTION IN A VIDEO SIGNAL. | |
| SE9403478D0 (en) | Component imaging | |
| JPH0844843A (en) | Analyzer for fish flow in fishway | |
| JPH08101017A (en) | Dimension measuring instrument | |
| JP4413342B2 (en) | 3D image detection device | |
| FI76645B (en) | FOERFARANDE FOER LOKALISERING OCH / ELLER IDENTIFIERING AV ETT OBJEKT. | |
| JPS60235068A (en) | Flow speed measuring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |